Telephoto zoom lens

ABSTRACT

A telephoto zoom lens comprising, in succession from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power, the lens groups being moved independently of each other during zooming. The telephoto zoom lens meets certain conditions, including a condition that prescribes the amount of change in spacing between the first and second lens groups by zooming, so that the spacing increases at the telephoto end. The telephoto ratio is large, and the lens is relatively compact at the wide angle end. The burden borne by each lens group regarding correction of spherical aberration is reduced, and correction of spherical aberration is relatively easy, so that the degree of freedom in lens design is enhanced.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a compact zoom lens, and in particularto improvements in a compact telephoto zoom lens which comprises, insuccession from the object side, three positive, negative and positivegroups.

2. Related Background Art

A telephoto zoom lens comprising, in succession from the object side,three groups having positive, negative and positive refractive powers isa developed form of the well-known telephoto zoom lens comprising fourpositive, negative, positive and positive groups. In a telephoto lens ofthe three-group construction of this type, the positive third group inthe conventional four-group construction for keeping the position of theimage surface constant and the positive fourth group which is an imaginggroup are made integral with each other to constitute a positive thirdlens group and further, the third lens group including the imaging groupis moved along the optic axis with the other lens groups during zooming,whereby a magnification changing operation may be accomplished.Accordingly, the magnification changing operation is borne in common bythe second lens group and the third lens group and therefore, the amountof magnification change by the negative second lens group which servedas the conventional magnification changing group, that is, the variationin magnification caused by the positional relation between the imagepoint of the first lens group and the second lens group during zooming,could be made smaller in this zoom lens of three-group construction thanin the conventional telephoto zoom lens of four-group construction.

In the conventional zoom lens of three-group construction of this type,however, if the refractive power of the first lens group is strengthenedto make the magnification changing system more compact, the imagingmagnification of the second lens group will become great and the imagepoint of the second lens group, namely, the object point of the thirdlens group, will move greatly toward the object side. Therefore, itbecomes difficult to sufficiently secure the spacing between the secondlens group and the third lens group with the focal length of the zoomlens being maximum at the telephoto end. Accordingly, to solve this, itbecomes necessary that the third lens group be made into a telephototype in which the telephoto ratio (the ratio of the full length to thefocal length) is extremely small. However, making the third lens groupwhich is the imaging group into a telephoto type in which the telephotoratio is extremely small has led to the disadvantage that it becomesdifficult to correct spherical aberration, particularly the sphericalaberration at the telephoto side on which the focal length is long.

Further, if the refractive power of the second lens group having anegative refractive power is strengthened to provide a compactconstruction, the positive refractive power component in the second lensgroup will be relatively weakened and it will become difficult to securethe degree of freedom of the aberration correction of the lens group.Therefore, it will become difficult to correct the fluctuation ofvarious aberrations caused by zooming. If in order to overcome this, anattempt is made to make the curvature of the joined surface of thenegative lens and the positive lens in the second lens group sharper andstrengthen the positive refractive power component, it has led to thedisadvantage that fluctuation of chromatic spherical aberration iscaused by zooming.

SUMMARY OF THE INVENTION

It is an object of the present invention to overcome the above-noteddisadvantages peculiar to the conventional telephoto zoom lens ofthree-group construction and to provide a very compact telephoto zoomlens having a good imaging performance over the entire range ofmagnification change.

The present invention is a telephoto zoom lens which comprises, insuccession from the object side, a first lens group having a positiverefractive power, a second lens group having a negative refractive powerand a third lens group having a positive refractive power, said lensgroups being moved independently of each other for a magnificationchange and focusing, and satisfying the following conditions: ##EQU1##where f_(w) : the focal length of the entire system at the wide end (theshortest focal length of the entire system)

f₁ : the focal length of the first lens group

f₂ : the focal length of the second lens group

f₃ : the focal length of the third lens group

β_(2W) : the imaging magnification at the wide end (the shortest focallength state of the entire system) of the second lens group

β_(2T) : the imaging magnification at the telephoto end (the longestfocal length state of the entire system) of the second lens group

β_(3W) : the imaging magnification at the wide end of the third lensgroup

β_(3T) : the imaging magnification at the telephoto end of the thirdlens group.

In the present invention, the first lens group is of relatively weakrefractive power. Thus, the object point of the third lens group can bemoved toward the image side and the imaging magnification of the secondlens group can be made small. If the imaging magnification of the secondlens group becomes small, the load of the second lens group foraberration correction can be mitigated and the refractive power of thesecond lens group can be more strengthened. Thereby, the magnificationchanging system can be constructed compactly in spite of the refractivepower of the first lens group having been weakened, and the object pointof the third lens group can be moved more toward the image side. In suchcase, if the refractive power of the second lens group is strengthened,the imaging magnification of the third lens group becomes great, thusresulting in bulkiness of the imaging system. However, the object pointof the third lens group moves greatly toward the image side and itbecomes unnecessary to make the third lens group into a telephoto typein which the telephoto ratio is extremely great and therefore, the loadof the third lens group for aberration correction is mitigated and therefractive power of the third lens group can be strengthened.Accordingly, the imaging system can be constructed compactly. In thismanner, success has been attained in making the lens system compactwithout making the third lens group into a telephoto type in which thetelephoto ratio is extremely great.

Expressions (1), (2) and (3) prescribe appropriate ranges of refractivepower of the respective lens groups. If the upper limit of expression(1) is exceeded, the refractive power of the first lens group willbecome too weak and it will become difficult to construct themagnification changing system compactly. If the lower limit ofexpression (1) is exceeded, the imaging magnification of the second lensgroup will become great and further, the object point of the third lensgroup will move toward the object side and it will become necessary tomake the third lens group into a telephoto type in which the telephotoratio is extremely great, and aberration correction will becomedifficult. If the upper limit of expression (2) is exceeded, it willbecome difficult to make the magnification changing system compact andfurther, the object point of the third lens group will move toward theobject side with a result that it will become necessary to make thethird lens group into a telephoto type in which the telephoto ratio isextremely great, and this is not preferable. If the lower limit ofexpression (2) is exceeded, Petzval sum will become excessively negativeand not only it will become difficult to correct astigmatism andcurvature of image field, but also the imaging magnification of thethird lens group will become excessively great, thus resulting inbulkiness of the imaging system. If the upper limit of expression (3) isexceeded, the imaging system will become bulky, and if the lower limitof expression (3) is exceeded, the refractive power of the third lensgroup will become excessively strong and correction of sphericalaberration will become difficult.

The inverse number of the imaging magnification of the second lens groupis indicative of the distance between the image point of the first lensgroup and the second lens group. Accordingly, expressions (4) and (5)prescribe the amount of magnification change borne by the second lensgroup due to the difference and ratio by zooming in the distance betweenthe image point of the first lens group and the second lens group. Ifthe upper limits of expressions (4) and (5) are exceeded, the amount ofmagnification change borne by the second lens group will become greatand therefore, the fluctuation of aberrations by zooming caused by themagnification changing action of the second lens group will also becomegreater and the aberration correction by the second lens group willbecome difficult. To solve this, the structure of the second lens groupmust be made more complex and therefore, it will become impossible tostrengthen the refractive power of the second lens group and it willbecome difficult to make the lens system compact.

The inverse number of the imaging magnification of the third lens groupis indicative of the distance between the image point of the second lensgroup and the third lens group. Accordingly, expressions (6) and (7)prescribe the amount of magnification change borne by the third lensgroup due to the difference and ratio by zooming in the distance betweenthe image point of the second lens group and the third lens group. Ifthe upper limits of expressions (6) and (7) are exceeded, the amount ofmagnification change borne by the third lens group will becomeexcessively great, and this is not preferable in aberration correction.If the lower limits of expressions (6) and (7) are exceeded, the amountof magnification change borne by the third lens group will becomeexcessively small and therefore, the amount of magnification changeborne by the second lens group must be made excessively great, and thisis not preferable.

As described above, according to the present invention, an appropriaterefractive power of each lens group and the imaging magnification duringzooming are provided as shown in the above-mentioned conditions (1)-(7), whereby there can be achieved a compact zoom lens having anexcellent imaging performance over the entire range of magnificationchange.

To balance the amount of magnification change borne by the second lensgroup with the amount of magnification change borne by the third lensgroup, it is desirable to provide the lower limits of conditions (4) and(5) as follows: ##EQU2##

Also, in the present invention as described above, it is furtherdesirable to make the third lens group into a construction as shownbelow. The third lens group is divided, in succession from the objectside, a forward positive lens group and a rearward negative lens group.Further, the forward positive lens group comprises, in succession fromthe object side, three positive lens components, i.e., a positive singlelens, a cemented lens consisting of a positive lens and a negative lenshaving its surface of sharper curvature facing the object side cementedtogether and having a positive refractive power, and a positive meniscuslens having its convex surface facing the object side, and it isdesirable to satisfy the following conditions:

    0.6<f.sub.3F /f.sub.3 <1.3                                 (8)

    1.5<|f.sub.3R /f.sub.3 |<8.5             (9)

    0.35<f.sub.3F /f.sub.31 <0.65                              (10)

where

f_(3F) : the focal length of the forward positive lens group in thethird lens group

f_(3R) : the focal length of the rearward negative lens group in thethird lens group

f₃₁ : the focal length of the first lens in the forward positive lensgroup in the third lens group.

Expressions (8), (9) and (10) prescribe the structure of the third lensgroup.

If the upper limit of expression (8) is exceeded, it will becomedifficult to make the third lens group compact. If the lower limit ofexpression (8) is exceeded, the relative aperture of the third lensgroup will become great and correction of spherical aberration willbecome difficult.

If the upper limit of expression (9) is exceeded, the full length of thethird lens group will become great and it will become difficult to makethe third lens group compact. If the lower limit of expression (9) isexceeded, Petzval sum will become excessively negative and correction ofastigmatism and curvature of image field will become difficult.

If the upper limit of expression (10) is exceeded, extroversive comawill occur and further, spherical aberration, particularly the sphericalaberration of the wide side, will become negative and the fluctuation ofspherical aberration by zooming will become excessively great, and thisis not preferable.

Also, where in the three-group telephoto zoom lens of the presentinvention which satisfies the above-mentioned conditions (1), (2) and(3), the second lens group is constructed of three lenses, in successionfrom the object side, namely, a negative first lens having its surfaceof sharper curvature facing the image side, a positive meniscus secondlens joined thereto and having its convex surface facing the objectside, and a negative third lens, it is desirable to satisfy thefollowing conditions: ##EQU3## where n₂₂ : the refractive index of thesecond lens in the second lens group

f₂ : the focal length of the second lens group

r₂₂ : the radius of curvature of the joined surface of the first lensand the second lens in the second lens group

r₂₄ : the radius of curvature of that surface of the third lens in thesecond lens group which is adjacent to the object side

r₂₅ : the radius of curvature of that surface of the third lens in thesecond lens group which is adjacent to the image side.

In this case, it becomes possible to make great the difference inrefractive index between the negative first lens and the positivemeniscus second lens constituting the cemented negative lens in thesecond lens group, thereby strengthening the positive refractive powerand securing the degree of freedom of aberration correction of the lensgroup. More specifically, it becomes possible to make the refractiveindex of the positive second lens higher and strengthen the positiverefractive power component in the second lens group and at the sametime, weaken the curvature of the joined surface of the first lens andthe second lens. Accordingly, it is possible to strengthen the positiverefractive power component in the second lens group and secure thedegree of freedom of aberration correction of the second lens groupwhile suppressing the fluctuation of chromatic spherical aberrationcaused by zooming, and it becomes easy to correct various aberrationswell while constructing the magnification changing system compactly.

The above-mentioned expression (11) prescribes an appropriate range ofrefractive index of the second lens in the second lens group. If theupper limit of expression (11) is exceeded, the range of refractiveindex of the ordinary glass material will be exceeded, and this is notpreferable. Also, if the positive refractive power component in thesecond lens group is weakened, the degree of freedom of aberrationcorrection of the second lens group will decrease and therefore, it isnot easy to strengthen the refractive power of the second lens group andthereby construct the magnification changing system compactly, and forthis reason, it is desirable that the lower limit of expression (11) benot exceeded.

Expression (12) prescribes the appropriate curvature of the joinedsurface of the first lens and the second lens in the second lens group,and to suppress the fluctuation of chromatic spherical aberration causedby zooming, it is desirable that the upper limit of expression (12) benot exceeded. If the lower limit of expression (12) is exceeded,achromatism will become difficult within the range of the existing glassmaterial.

Expression (13) prescribes the shape of the third lens in the secondlens group. If the upper limit of expression (13) is exceeded,astigmatism will become excessively positive and introversive coma willoccur, and this is not preferable. If the lower limit of expression (13)is exceeded, astigmatism will become excessively negative andextroversive coma will occur, and this is not preferable.

Further objects, features and effects of the present invention willbecome fully apparent from the following detailed description taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a lens construction according to a first embodiment of thepresent invention.

FIG. 2 shows a lens construction used for the description of second,third and fourth embodiments of the present invention.

FIG. 3 shows a lens construction according to a fifth embodiment of thepresent invention.

FIG. 4 shows a lens construction according to a sixth embodiment of thepresent invention.

FIG. 5 shows a lens construction according to a seventh embodiment ofthe present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In a first embodiment of the present invention which is shown in FIG. 1,a first lens group G1 having a positive refractive power comprises, insuccession from the object side, a negative meniscus lens L11 having itsconvex surface facing the object side, a biconvex positive lens L12joined thereto and a biconvex positive lens L13, a second lens group G2having a negative refractive power comprises, in succession from theobject side, a negative first lens L21 having its surface of sharpercurvature facing the image side, a positive meniscus second lens L22joined thereto and having its convex surface facing the object side, anda negative third lens L23 having its surface of sharper curvature facingthe object side, a forward group G3F in a third lens group G3 having apositive refractive power comprises a positive lens L31 having itssurface of sharper curvature facing the image side, a biconvex positivelens L32, a negative meniscus lens L33 joined thereto and having itsconvex surface facing the image side, and a positive meniscus lens L34having its convex surface facing the object side, and a rearward groupG3R in the third lens group G3 comprises a negative lens L35 having itssurface of sharper curvature facing the image side, and a biconvexpositive lens L36.

In the first embodiment, as shown in FIG. 1, a stop S is disposedbetween the forward group G3F and the rearward group G3R in the thirdlens group G3.

Also shown in FIG. 1 is the movement locus of each lens group whenzooming is effected from the wide angle side to the telephoto side. Thefirst lens group G1 is linearly moved toward the object side, the secondlens group G2 is moved toward the image side while depicting a convexnon-linear locus, and the third lens group G3 is non-linearly movedtoward the object side.

The numerical data of the first embodiment of the present invention willbe shown below. In the table below, the numbers at the left endrepresent the order from the object side, f represents the focal lengthof the entire system, and Bf represents the back focal length.

    __________________________________________________________________________    First Embodiment                                                              f = 71.500-205.000                                                            F-number 4.1-5.5                                                              __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________     1 r.sub.11                                                                        153.845                                                                              d.sub.1                                                                         2.300 n.sub.11                                                                        1.80458                                                                           25.5 L.sub.11                                        2 r.sub.12                                                                        71.737 d.sub.2                                                                         5.800 n.sub.12                                                                        1.51680                                                                           64.1 L.sub.12                                        3 r.sub.13                                                                        -449.462                                                                             d.sub.3                                                                         0.100                 G.sub.1                                    4 r.sub.14                                                                        107.481                                                                              d.sub.4                                                                         4.600 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                        5 r.sub.15                                                                        -278.364                                                                             d.sub.5                                                                         (variable)                                                       6 r.sub.21                                                                        -228.633                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.69350                                                                           53.8 L.sub.21                                        7 r.sub.22                                                                        18.350 d.sub.7                                                                         4.000 n.sub.22                                                                        1.80458                                                                           25.5 L.sub.22                                        8 r.sub.23                                                                        45.502 d.sub.8                                                                         3.800                 G.sub.2                                    9 r.sub.24                                                                        -33.847                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.69350                                                                           53.8 L.sub.23                                       10 r.sub.25                                                                        550.868                                                                              d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        104.039                                                                              d.sub.11                                                                        4.200 n.sub.31                                                                        1.49782                                                                           82.6 L.sub.31                                       12 r.sub.32                                                                        -38.434                                                                              d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        52.401 d.sub.13                                                                        5.500 n.sub.32                                                                        1.48749                                                                           70.2 L.sub.32                                       14 r.sub.34                                                                        -31.880                                                                              d.sub.14                                                                        1.400 n.sub.33                                                                        1.74000                                                                           28.3 L.sub.33                                       15 r.sub.35                                                                        -126.224                                                                             d.sub.15                                                                        0.800                                                           16 r.sub.36                                                                        32.945 d.sub.16                                                                        4.600 n.sub.34                                                                        1.62041                                                                           60.3 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        182.768                                                                              d.sub.17                                                                        13.100                                                          18 r.sub.38                                                                        -181.312                                                                             d.sub.18                                                                        1.600 n.sub.35                                                                        1.76684                                                                           46.8 L.sub.35                                       19 r.sub.39                                                                        24.638 d.sub.19                                                                        9.800                                                           20 r.sub.40                                                                        113.747                                                                              d.sub.20                                                                        3.200 n.sub.36                                                                        1.62588                                                                           35.6 L.sub.36                                       21 r.sub.41                                                                        -66.352                                                                  __________________________________________________________________________    f      71.500        115.000                                                                           205.000                                              __________________________________________________________________________    d 5    1.782         24.276                                                                            38.607                                               d 10   16.005        9.748                                                                             0.640                                                B f    55.650        63.190                                                                            83.289                                               __________________________________________________________________________                 f.sub.1 /f.sub.W = 1.566                                                      |f.sub.2 /f.sub.W | = 0.373                                 f.sub.3 /f.sub.W = 0.483                                                       ##STR1##                                                                     β.sub.2W /β.sub.2T = 0.505                                           ##STR2##                                                                     β.sub.3W /β.sub.3T = 0.690                                          f.sub.3F /f.sub.3 = 0.757                                                     |f.sub.3R /f.sub.3 | = 1.963                                f.sub.3F /f.sub.31 = 0.459                                       __________________________________________________________________________

The above values satisfy the conditions of expressions (1)-(10), (4')and (5').

The values of conditions (11)-(13) about the second lens group G2 are asfollows: ##EQU4## n₂₂ slightly deviates from the lower limit ofcondition (11), and r₂₂ /f₂ slightly deviates from the upper limit ofcondition (12). When extremely precise depiction is required as when aphotograph is greatly enlarged and used, it is desirable to set thevalues of n₂₂ and r₂₂ within the ranges of conditions (11) and (12) inorder to suppress the fluctuation of chromatic spherical aberrationduring zooming.

FIG. 2 shows the lens construction according to second, third and fourthembodiments of the present invention. In FIG. 2, a first lens group G1comprises, in succession from the object side, a positive lens L11having its surface of sharper curvature facing the object side, anegative meniscus lens L12 having its convex surface facing the objectside and a positive lens L13 joined thereto and having its convexsurface of sharper curvature facing the object side, a second lens groupG2 comprises, in succession from the object side, a negative first lensL21 having its surface of sharper curvature facing the image side, apositive meniscus second lens L22 joined thereto and having its convexsurface facing the object side and a negative lens L23 having itssurface of sharper curvature facing the object side, a forward group G3Fin a third lens group G3 comprises, in succession from the object side,a positive lens L31 having its convex surface of sharper curvaturefacing the image side, a biconvex positive lens L32, a negative lens L33joined thereto and having its surface of sharper curvature facing theobject side and a positive meniscus lens L34 having its convex surfacefacing the object side, and a rearward group G3R in the third lens groupcomprises a negative meniscus lens L35 having its convex surface facingthe image side and a positive lens L36 having its surface of sharpercurvature facing the image side.

A variable stop S1 and a fixed stop S2 are disposed between the forwardgroup G3F and the rearward group G3R in the third lens group G3.

Also shown in FIG. 2 is the movement locus of each lens group whenzooming is effected from the wide angle side to the telephoto side. Thefirst lens group is linearly moved toward the object side, the secondlens group is moved toward the image side while depicting a convexnon-linear locus, and the third lens group is non-linearly moved towardthe object side. The numerical data of the second, third and fourthembodiments of the present invention will be shown below.

    __________________________________________________________________________    Second Embodiment                                                             f = 71.500-205.000                                                            F-number 4.1-5.5                                                              __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________     1 r.sub.11                                                                        120.465                                                                              d.sub.1                                                                         3.700 n.sub.11                                                                        1.51680                                                                           64.1 L.sub.11                                        2 r.sub.12                                                                        1885.001                                                                             d.sub.2                                                                         0.100                                                            3 r.sub.13                                                                        87.589 d.sub.3                                                                         2.000 n.sub.12                                                                        1.80458                                                                           25.5 L.sub.12                                                                           G.sub.1                                    4 r.sub.14                                                                        52.453 d.sub.4                                                                         7.600 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                        5 r.sub.15                                                                        -413.504                                                                             d.sub.5                                                                         (variable)                                                       6 r.sub.21                                                                        -150.683                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.65160                                                                           58.5 L.sub.21                                        7 r.sub.22                                                                        20.543 d.sub.7                                                                         3.400 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                        8 r.sub.23                                                                        36.361 d.sub.8                                                                         4.200                 G.sub.2                                    9 r.sub.24                                                                        -35.217                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.65160                                                                           58.5 L.sub.23                                       10 r.sub.25                                                                        5931.968                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        106.024                                                                              d.sub.11                                                                        4.500 n.sub.31                                                                        1.50137                                                                           56.5 L.sub. 31                                      12 r.sub.32                                                                        -37.807                                                                              d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        65.312 d.sub.13                                                                        5.300 n.sub.32                                                                        1.51860                                                                           70.1 L.sub.32                                       14 r.sub.34                                                                        -31.533                                                                              d.sub.14                                                                        1.400 n.sub.33                                                                        1.75520                                                                           27.6 L.sub.33                                       15 r.sub.35                                                                        -393.056                                                                             d.sub.15                                                                        0.800                                                           16 r.sub.36                                                                        29.359 d.sub.16                                                                        3.600 n.sub.34                                                                        1.69350                                                                           53.8 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        46.171 d.sub.17                                                                        40.200                                                          18 r.sub.38                                                                        -18.228                                                                              d.sub.18                                                                        2.100 n.sub.35                                                                        1.77279                                                                           49.4 L.sub.35                                       19 r.sub.39                                                                        -29.161                                                                              d.sub.19                                                                        0.200                                                           20 r.sub.40                                                                        1024.571                                                                             d.sub.20                                                                        2.800 n.sub.36                                                                        1.69895                                                                           30.1 L.sub.36                                       21 r.sub.41                                                                        -73.471                                                                  __________________________________________________________________________    f      71.500        115.000                                                                           205.000                                              __________________________________________________________________________    d 5    1.400         24.501                                                                            36.417                                               d 10   16.800        10.418                                                                            0.946                                                B f    41.267        46.675                                                                            69.107                                               __________________________________________________________________________                 f.sub.1 /f.sub.W = 1.567                                                      |f.sub.2 /f.sub.W|  = 0.373                                 f.sub.3 /f.sub.W = 0.483                                                       ##STR3##                                                                     β.sub.2W /β.sub.2T = 0.513                                           ##STR4##                                                                     β.sub.3W / β.sub.3T = 0.680                                         f.sub.3F /f.sub.3 = 0.989                                                     |f.sub.3R /f.sub.3 | = 8.028                                f.sub.3F /f.sub.31 = 0.607                                       __________________________________________________________________________

The above values satisfy conditions (1)-(10), (4') and (5').

Also,

n₂₂ =1.86074

r₂ /f₂ =-0.770

(r₂₅ +r₂₄)/(r.sub. -r₂₄)=0.9867

The above values satisfy conditions (11)-(13).

    __________________________________________________________________________    Third Embodiment                                                              f = 71.500-205.000                                                            F-number 4.1-5.5                                                              __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________     1 r.sub.11                                                                        124.745                                                                              d.sub.1                                                                         3.700 n.sub.11                                                                        1.51680                                                                           64.1 L.sub.11                                        2 r.sub.12                                                                        4325.365                                                                             d.sub.2                                                                         0.100                                                            3 r.sub.13                                                                        87.610 d.sub.3                                                                         2.000 n.sub.12                                                                        1.80458                                                                           25.5 L.sub.12                                                                           G.sub.1                                    4 r.sub.14                                                                        52.453 d.sub.4                                                                         7.700 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                        5 r.sub.15                                                                        -416.542                                                                             d.sub.5                                                                         (variable)                                                       6 r.sub.21                                                                        -150.751                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.65160                                                                           58.5 L.sub.21                                        7 r.sub.22                                                                        20.543 d.sub.7                                                                         3.400 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                        8 r.sub.23                                                                        36.370 d.sub.8                                                                         4.200                 G.sub.2                                    9 r.sub.24                                                                        -35.484                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.65160                                                                           58.5 L.sub.23                                       10 r.sub.25                                                                        2543.972                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        103.308                                                                              d.sub.11                                                                        4.500 n.sub.31                                                                        1.50137                                                                           56.5 L.sub.31                                       12 r.sub.32                                                                        -38.149                                                                              d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        64.331 d.sub.13                                                                        5.300 n.sub.32                                                                        1.51860                                                                           70.1 L.sub.32                                       14 r.sub.34                                                                        -31.533                                                                              d.sub.14                                                                        1.400 n.sub.33                                                                        1.75520                                                                           27.6 L.sub.33                                       15 r.sub.35                                                                        -368.870                                                                             d.sub.15                                                                        0.800                                                           16 r.sub.36                                                                        29.048 d.sub.16                                                                        3.600 n.sub.34                                                                        1.69350                                                                           53.8 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        44.423 d.sub.17                                                                        40.200                                                          18 r.sub.38                                                                        -18.138                                                                              d.sub.18                                                                        2.100 n.sub.35                                                                        1.76684                                                                           46.8 L.sub.35                                       19 r.sub.39                                                                        -28.876                                                                              d.sub.19                                                                        0.200                                                           20 r.sub.40                                                                        -4032.012                                                                            d.sub.20                                                                        2.800 n.sub.36                                                                        1.72825                                                                           28.3 L.sub.36                                       21 r.sub.41                                                                        -71.662                                                                  __________________________________________________________________________    f      71.500        135.000                                                                           205.006                                              __________________________________________________________________________    d 5    1.741         28.503                                                                            36.546                                               d 10   16.985        7.923                                                                             1.065                                                B f    40.922        51.636                                                                            68.755                                               __________________________________________________________________________                 f.sub.1 /f.sub.W = 1.567                                                      |f.sub.2 /f.sub.W | = 0.373                                 f.sub.3 /f.sub.W = 0.483                                                       ##STR5##                                                                     β.sub.2W /β.sub.2T = 0.513                                           ##STR6##                                                                     β.sub.3W /β.sub.3T = 0.679                                          f.sub.3F /f.sub.2 = 0.989                                                     |f.sub.3R /f.sub.3 | = 7.957                                f.sub.3F /f.sub.31 = 0.608                                       __________________________________________________________________________

The above values satisfy conditions (1)-(10), (4') and (5').

Also,

n₂₂ =1.86074

r₂ /f₂ =-0.770

(r₂₅ +r₂₄)/(r₂₅ -r₂₄)=0.9725

The above values satisfy conditions (11)-(13).

    __________________________________________________________________________    Fourth Embodiment                                                             f = 71.500-204.999                                                            F-number 4.1-5.5                                                              __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________     1 r.sub.11                                                                        98.438 d.sub.1                                                                         3.500 n.sub.11                                                                        1.46450                                                                           65.8 L.sub.11                                        2 r.sub.12                                                                        802.616                                                                              d.sub.2                                                                         0.100                                                            3 r.sub.13                                                                        76.116 d.sub.3                                                                         2.000 n.sub.12                                                                        1.80458                                                                           25.5 L.sub.12                                                                           G.sub.1                                    4 r.sub.14                                                                        44.695 d.sub.4                                                                         7.300 n.sub.13                                                                        1.51835                                                                           60.3 L.sub.13                                        5 r.sub.15                                                                        -279.389                                                                             d.sub.5                                                                         (variable)                                                       6 r.sub.21                                                                        -128.684                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.65160                                                                           58.5 L.sub.21                                        7 r.sub.22                                                                        20.994 d.sub.7                                                                         3.200 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                        8 r.sub.23                                                                        37.184 d.sub.8                                                                         4.100                 G.sub.2                                    9 r.sub.24                                                                        -37.845                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.65160                                                                           58.5 L.sub.23                                       10 r.sub.25                                                                        6107.025                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        119.160                                                                              d.sub.11                                                                        4.300 n.sub.31                                                                        1.50137                                                                           56.5 L.sub.31                                       12 r.sub.32                                                                        -37.088                                                                              d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        71.445 d.sub.13                                                                        5.300 n.sub.32                                                                        1.51860                                                                           70.1 L.sub.32                                       14 r.sub.34                                                                        -29.228                                                                              d.sub.14                                                                        1.400 n.sub.33                                                                        1.75520                                                                           27.6 L.sub.33                                       15 r.sub.35                                                                        -333.136                                                                             d.sub.15                                                                        0.800                                                           16 r.sub.36                                                                        22.903 d.sub.16                                                                        3.600 n.sub.34                                                                        1.54814                                                                           45.9 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        38.213 d.sub.17                                                                        34.800                                                          18 r.sub.38                                                                        -15.897                                                                              d.sub.18                                                                        2.100 n.sub.35                                                                        1.77279                                                                           49.4 L.sub.35                                       19 r.sub.39                                                                        -24.699                                                                              d.sub.19                                                                        0.200                                                           20 r.sub.40                                                                        -306.837                                                                             d.sub.20                                                                        2.800 n.sub.36                                                                        1.86074                                                                           23.0 L.sub.36                                       21 r.sub.41                                                                        -82.419                                                                  __________________________________________________________________________    f      71.500        135.000                                                                           204.999                                              __________________________________________________________________________    d 5    2.250         22.806                                                                            29.375                                               d 10   19.898        8.849                                                                             0.957                                                B f    41.337        53.103                                                                            69.563                                               __________________________________________________________________________                 f.sub.1 /f.sub.W = 1.385                                                      |f.sub.2 /f.sub.W | = 0.381                                 f.sub.3 /f.sub.W = 0.483                                                       ##STR7##                                                                     β.sub.2W /β.sub.2T = 0.534                                           ##STR8##                                                                     β.sub.3W /β.sub.3T = 0.653                                          f.sub.3F /f.sub.3 = 0.996                                                     |f.sub.3R /f.sub.3 | = 4.065                                f.sub.3F /f.sub.31 = 0.603                                                    n.sub.22 = 1.86074                                                            r.sub.22 /f.sub.2 = -0.769                                                     ##STR9##                                                        __________________________________________________________________________

The above values satisfy conditions (1)-(13).

In a fifth embodiment of the present invention, as shown in FIG. 3, afirst lens group G1 comprises, in succession from the object side, anegative meniscus lens L11 having its convex surface facing the objectside, a positive lens L12 joined thereto and having its surface ofsharper curvature facing the object side, and a biconvex positive lensL13, a second lens group G2 comprises, in succession from the objectside, a negative first lens L21 having its surface of sharper curvaturefacing the image side, a positive meniscus second lens L22 joinedthereto and having its convex surface facing the object side, and anegative third lens L23 having its surface of sharper curvature facingthe object side, and a third lens group G3 comprises a forward group G3Fcomprising, in succession from the object side, a biconvex positive lensL31, a biconvex positive lens L32, a biconvex positive lens L33 and abiconcave negative lens L34 joined thereto, and a rearward group G3Rcomprising a negative meniscus lens L35 having its surface of sharpercurvature facing the object side and a positive lens L36 having itssurface of sharper curvature facing the image side.

In the fifth embodiment, as shown in FIG. 3, a variable stop S1 and afixed stop S2 are provided between the forward group G3F and therearward group G3R in the third lens group G3.

Also shown in FIG. 3 is the movement locus of each lens group whenzooming is effected from the wide angle side to the telephoto side. Thefirst lens group is linearly moved toward the object side, the secondlens group is moved toward the image side while depicting a convexnon-linear locus, and the third lens group is non-linearly moved towardthe object side.

The numerical data of the fifth embodiment of the present invention willbe shown below. In the table below, the numbers at the left endrepresent the order from the object side, f represents the focal lengthof the entire system, and Bf represents the back focal length.

    __________________________________________________________________________    Fifth Embodiment                                                              __________________________________________________________________________    f = 71.500-205.000                                                            F-number 4.1-5.5                                                              __________________________________________________________________________       Radius of                                                                             Center thickness                                                                       Refractive                                                                           Abbe                                                  curvature                                                                             and space                                                                              index  number                                             No.                                                                              r       d        n      ν                                               __________________________________________________________________________     1 r.sub.11                                                                         118.310                                                                            d.sub.1                                                                          2.300 n.sub.11                                                                         1.80458                                                                           25.5 L.sub.11                                       2 r.sub.12                                                                         63.790                                                                             d.sub.2                                                                          6.000 n.sub.12                                                                         1.51680                                                                           64.1 L.sub.12                                       3 r.sub.13                                                                         1325.679                                                                           d.sub.3                                                                          0.100                  G.sub.1                                   4 r.sub.14                                                                         95.278                                                                             d.sub.4                                                                          5.400 n.sub.13                                                                         1.51680                                                                           64.1 L.sub.13                                       5 r.sub.15                                                                         -289.179                                                                           d.sub.5                                                                          (variable)                                                       6 r.sub.21                                                                         -155.511                                                                           d.sub.6                                                                          1.200 n.sub.21                                                                         1.65160                                                                           58.5 L.sub.21                                       7 r.sub.22                                                                         20.550                                                                             d.sub.7                                                                          3.400 n.sub.22                                                                         1.86074                                                                           23.0 L.sub.22                                       8 r.sub.23                                                                         36.637                                                                             d.sub.8                                                                          4.200                  G.sub.2                                   9 r.sub.24                                                                         -34.912                                                                            d.sub.9                                                                          1.200 n.sub.23                                                                         1.65160                                                                           58.5 L.sub.23                                      10 r.sub.25                                                                         2426.367                                                                           d.sub.10                                                                         (variable)                                                      11 r.sub.31                                                                         115.890                                                                            d.sub.11                                                                         3.500 n.sub. 31                                                                        1.51860                                                                           70.1 L.sub.31                                      12 r.sub.32                                                                         -84.561                                                                            d.sub.12                                                                         0.200                                                           13 r.sub.33                                                                         50.935                                                                             d.sub.13                                                                         4.300 n.sub.32                                                                         1.48749                                                                           70.2 L.sub.32                                      14 r.sub.34                                                                         -88.680                                                                            d.sub.14                                                                         0.800                                                           15 r.sub.35                                                                         38.863                                                                             d.sub.15                                                                         5.200 n.sub.33                                                                         1.51680                                                                           64.1 L.sub.33                                                                           G.sub.3                                  16 r.sub.36                                                                         -54.825                                                                            d.sub.16                                                                         1.400 n.sub.34                                                                         1.78470                                                                           26.1 L.sub.34                                      17 r.sub.37                                                                         145.469                                                                            d.sub.17                                                                         39.800                                                          18 r.sub.38                                                                         -19.312                                                                            d.sub.18                                                                         2.100 n.sub.35                                                                         1.77279                                                                           49.4 L.sub.35                                      19 r.sub.39                                                                         -32.084                                                                            d.sub.19                                                                         0.200                                                           20 r.sub.40                                                                         -701.705                                                                           d.sub.20                                                                         2.800 n.sub.36                                                                         1.74077                                                                           27.6 L.sub.36                                      21 r.sub.41                                                                         -64.629                                                                 __________________________________________________________________________    f            71.500   115.000  205.000                                        d 5          1.586    25.921   37.783                                         d 10         17.300   11.136   1.853                                          B f          42.725   47.511   70.890                                         __________________________________________________________________________                f.sub.1 /f.sub.W = 1.566                                                      |f.sub.2 /f.sub.W | = 0.373                                 f.sub.3 /f.sub.W = 0.483                                                       ##STR10##                                                                    β.sub.2W /β.sub.2T = 0.509                                           ##STR11##                                                                    β.sub.3W /β.sub.3T = 0.684                                          f.sub.3F /f.sub.3 = 0.989                                                     |f.sub.3R /f.sub.3 | = 8.131                                f.sub.3F f.sub.31 = 0.360                                                     n.sub.22 = 1.86074                                                            r.sub.22 /f.sub.2 = -0.770                                                     ##STR12##                                                        __________________________________________________________________________

The above values satisfy conditions (1)-(13), (4') and (5').

FIG. 4 shows a lens construction according to a sixth embodiment of thepresent invention in which the second lens group G2 in the firstembodiment shown in FIG. 1 is improved to satisfy conditions (11)-(13).

In FIG. 4, a first lens group G1 comprises, in succession from theobject side, a negative meniscus lens L11 having its convex surfacefacing the object side, a positive lens L12 joined thereto and havingits surface of sharper curvature facing the object side, and a biconvexpositive lens L13, a second lens group G2 comprises, in succession fromthe object side, a negative first lens L21 having its surface of sharpercurvature facing the image side, a positive meniscus second lens L22joined thereto and having its convex surface facing the object side, anda negative third lens L23 having its surface of sharper curvature facingthe image side, and a third lens group G3 comprises a forward group G3Fcomprising, in succession from the object side, a positive lens L31having its surface of sharper curvature facing the image side, abiconvex positive lens L32, a negative meniscus lens L33 joined theretoand having its convex surface facing the image side, and a positivemeniscus lens L34 having its convex surface facing the object side, anda rearward group G3R comprising a negative lens L35 having its surfaceof sharper curvature facing the image side and a positive lens L36having its surface of sharper curvature facing the image side.

In the sixth embodiment, as shown in FIG. 4, a stop S is disposedbetween the forward group G3F and the rearward group G3R in the thirdlens group G3.

Also shown in FIG. 4 is the movement locus of each lens group whenzooming is effected from the wide angle side to the telephoto side. Thefirst lens group is linearly moved toward the object side, the secondlens group is moved toward the image side while depicting a convexnon-linear locus, and the third lens group is non-linearly moved towardthe object side.

The numerical data of the sixth embodiment of the present invention willbe shown below.

    __________________________________________________________________________    Sixth Embodiment                                                              __________________________________________________________________________                   f = 71.500-205.000                                                            F-number 4.1-5.5                                               __________________________________________________________________________       Radius of                                                                             Center thickness                                                                       Refractive                                                                           Abbe                                                  curvature                                                                             and space                                                                              index  number                                             No.                                                                              r       d        n      ν                                               __________________________________________________________________________     1 r.sub.11                                                                         153.844                                                                            d.sub.1                                                                          2.300 n.sub.11                                                                         1.80458                                                                           25.5 L.sub.11                                       2 r.sub.12                                                                         71.737                                                                             d.sub.2                                                                          5.800 n.sub.12                                                                         1.51680                                                                           64.1 L.sub.12                                       3 r.sub.13                                                                         -449.461                                                                           d.sub.3                                                                          0.100                  G.sub.1                                   4 r.sub.14                                                                         107.481                                                                            d.sub.4                                                                          4.600 n.sub.13                                                                         1.51680                                                                           64.1 L.sub.13                                       5 r.sub.15                                                                         -278.364                                                                           d.sub.5                                                                          (variable)                                                       6 r.sub.21                                                                         -207.164                                                                           d.sub.6                                                                          1.200 n.sub.21                                                                         1.69350                                                                           53.8 L.sub.21                                       7 r.sub.22                                                                         20.395                                                                             d.sub.7                                                                          4.000 n.sub.22                                                                         1.86074                                                                           23.0 L.sub.22                                       8 r.sub.23                                                                         40.805                                                                             d.sub.8                                                                          4.000                  G.sub.2                                   9 r.sub.24                                                                         -32.559                                                                            d.sub.9                                                                          1.200 n.sub.23                                                                         1.69350                                                                           53.8 L.sub.23                                      10 r.sub.25                                                                         -687.887                                                                           d.sub.10                                                                         (variable)                                                      11 r.sub.31                                                                         104.039                                                                            d.sub.11                                                                         4.200 n.sub.31                                                                         1.49782                                                                           82.6 L.sub.31                                      12 r.sub.32                                                                         -38.434                                                                            d.sub.12                                                                         0.200                                                           13 r.sub.33                                                                         52.401                                                                             d.sub.13                                                                         5.500 n.sub.32                                                                         1.48749                                                                           70.2 L.sub.32                                      14 r.sub.34                                                                         -31.880                                                                            d.sub.14                                                                         1.400 n.sub.33                                                                         1.74000                                                                           28.3 L.sub.33                                      15 r.sub.35                                                                         -126.223                                                                           d.sub.15                                                                         0.800                  G.sub.3                                  16 r.sub.36                                                                         32.945                                                                             d.sub.16                                                                         4.600 n.sub.34                                                                         1.62041                                                                           60.3 L.sub.34                                      17 r.sub.37                                                                         182.768                                                                            d.sub.17                                                                         13.100                                                          18 r.sub.38                                                                         -181.312                                                                           d.sub.18                                                                         1.600 n.sub.35                                                                         1.76684                                                                           46.8 L.sub.35                                      19 r.sub.39                                                                         24.638                                                                             d.sub.19                                                                         9.800                                                           20 r.sub.40                                                                         113.747                                                                            d.sub.20                                                                         3.200 n.sub.36                                                                         1.62588                                                                           35.6 L.sub.36                                      21 r.sub.41                                                                         -66.352                                                                 __________________________________________________________________________    f            71.500   115.000  205.000                                        d 5          1.825    24.320   38.650                                         d 10         15.816   9.559    0.452                                          B f          55.650   63.190   83.289                                         __________________________________________________________________________                f.sub.1 /f.sub.W = 1.566                                                      |f.sub.2 /f.sub.W | = 0.373                                 f.sub.3 /f.sub.W = 0.483                                                       ##STR13##                                                                    β.sub.2W /β.sub.2T = 0.505                                           ##STR14##                                                                    β.sub.3W /β.sub.3T = 0.690                                          f.sub.3F /f.sub.3 = 0.757                                                     |f.sub.3R /f.sub.3 | = 1.963                                f.sub.3F /f.sub.31 = 0.459                                                    n.sub.22 = 1.86074                                                            r.sub.22 /f.sub.2 = -0.764                                                     ##STR15##                                                        __________________________________________________________________________

The above values all satisfy conditions (1)-(13), (4') and (5').

FIG. 5 shows a lens construction according to a seventh embodiment ofthe present invention in which the construction of the forward group G3Fin the third lens group shown in FIG. 3 is changed.

In FIG. 5, a first lens group G1 comprises, in succession from theobject side, a positive lens L11 having its surface of sharper curvaturefacing the object side, a negative meniscus lens L12 having its convexsurface facing the object side, and a positive lens L13 joined theretoand having its surface of sharper curvature facing the object side, asecond lens group G2 comprises, in succession from the object side, anegative first lens L21 having its surface of sharper curvature facingthe image side, a positive meniscus second lens L22 joined thereto andhaving its convex surface facing the object side, and a negative thirdlens L23 having its surface of sharper curvature facing the object side,and a third lens group G3 comprises a forward group G3F comprising, insuccession from the object side, a positive lens L31 having its surfaceof sharper curvature facing the image side, a negative meniscus lens L32joined thereto and having its convex surface facing the image side, abiconvex positive lens L33 having its surface of sharper curvaturefacing the object side, and a negative lens L34 having its surface ofsharper curvature facing the object side, and a rearward group G3Rcomprising a negative meniscus lens L35 having its convex surface facingthe image side and a positive lens L36 having its surface of sharpercurvature facing the image side. A variable stop S1 and a fixed stop S2are provided between the forward group G3F and the rearward group G3R.

As described above, in the seventh embodiment, the forward group G3F inthe third lens group G3 entirely differs from the constructions shown inFIGS. 1 to 4. Therefore, condition (10) is not satisfied. However, comaand spherical aberration based on condition (10) are corrected well bythe unique construction of the forward group G3F.

Also shown in FIG. 5 is the movement locus of each lens group whenzooming is effected from the wide angle side to the telephoto side. Thefirst lens group is linearly moved toward the object side, the secondlens group is moved toward the image side while depicting a convexnon-linear locus, and the third lens group is non-linearly moved towardthe object side.

The numerical data of the seventh embodiment of the present inventionwill be shown below.

    __________________________________________________________________________    Seventh Embodiment                                                            f = 72.318-205.565                                                            F-number 4.5-5.0                                                              __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________     1 r.sub.11                                                                        107.200                                                                              d.sub.1                                                                         3.850 n.sub.11                                                                        1.51680                                                                           64.1 L.sub.11                                        2 r.sub.12                                                                        -1450.001                                                                            d.sub.2                                                                         0.200                                                            3 r.sub.13                                                                        79.420 d.sub.3                                                                         1.950 n.sub.12                                                                        1.80518                                                                           25.4 L.sub.12                                                                           G.sub.1                                    4 r.sub.14                                                                        47.810 d.sub.4                                                                         6.300 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                        5 r.sub.15                                                                        -1449.991                                                                            d.sub.5                                                                         (variable)                                                       6 r.sub.21                                                                        -203.083                                                                             d.sub.6                                                                         1.000 n.sub.21                                                                        1.69680                                                                           55.6 L.sub.21                                        7 r.sub.22                                                                        20.547 d.sub.7                                                                         3.860 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                        8 r.sub.23                                                                        37.163 d.sub.8                                                                         3.200                 G.sub.2                                    9 r.sub.24                                                                        -38.171                                                                              d.sub.9                                                                         1.000 n.sub.23                                                                        1.69680                                                                           55.6 L.sub.23                                       10 r.sub.25                                                                        -497.113                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        85.720 d.sub.11                                                                        4.550 n.sub.31                                                                        1.61272                                                                           58.6 L.sub. 31                                      12 r.sub.32                                                                        -31.160                                                                              d.sub.12                                                                        1.000 n.sub.32                                                                        1.71736                                                                           29.5 L.sub.32                                       13 r.sub.33                                                                        -54.350                                                                              d.sub.13                                                                        0.200                                                           14 r.sub.34                                                                        27.615 d.sub.14                                                                        5.160 n.sub.33                                                                        1.48749                                                                           70.2 L.sub.33                                       15 r.sub.35                                                                        -88.000                                                                              d.sub.15                                                                        2.940                                                           16 r.sub.36                                                                        -55.000                                                                              d.sub.16                                                                        2.000 n.sub.34                                                                        1.75520                                                                           27.6 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        0.000  d.sub.17                                                                        36.100                                                          18 r.sub.38                                                                        -17.300                                                                              d.sub.18                                                                        1.270 n.sub.35                                                                        1.69680                                                                           55.6 L.sub.35                                       19 r.sub.39                                                                        -30.500                                                                              d.sub.19                                                                        0.200                                                           20 r.sub.40                                                                        700.000                                                                              d.sub.20                                                                        2.480 n.sub.36                                                                        1.71736                                                                           29.5 L.sub.36                                       21 r.sub.41                                                                        -68.001                                                                  __________________________________________________________________________    f      72.818        133.831                                                                           205.565                                              __________________________________________________________________________    d 5    .939          25.106                                                                            32.939                                               d 10   20.091        10.046                                                                            1.650                                                B f    42.052        49.813                                                                            64.511                                               __________________________________________________________________________                 f.sub.1 /f.sub.W = 1.422                                                      |f.sub.2 /f.sub.W | = 0.380                                 f.sub.3 /f.sub.W = 0.478                                                       ##STR16##                                                                    β.sub.2W /β.sub.2T = 0.496                                           ##STR17##                                                                    β.sub.3W /β.sub.3T = 0.714                                          f.sub.3F /f.sub.3 = 1.008                                                     |f.sub.3R /f.sub.3 | = 6.325                                n.sub.22 = 1.86074                                                            r.sub.22 /f.sub.2 = -0.742                                                     ##STR18##                                                       __________________________________________________________________________

The above values satisfy conditions (1)-(9) and (11)-(13) exceptcondition (10).

What is claimed is:
 1. A telephoto zoom lens comprising, in successionfrom the object side, a first lens group having a positive refractivepower, a second lens group having a negative refractive power, and athird lens group having a positive refractive power, said lens groupbeing moved independently of each other during zooming and satisfyingthe following conditions: ##EQU5## where f_(W) : the focal length of theentire system at the wide endf₁ : the focal length of the first lensgroup f₂ : the focal length of the second lens group f₃ : the focallength of the third lens group β_(2W) : the imaging magnification at thewide end of the second lens group β_(2T) : the imaging magnification atthe telephoto end of the second lens group β_(3W) : the imagingmagnification at the wide end of the third lens group β_(3T) : theimaging magnification at the telephoto end of the third lens group.
 2. Atelephoto zoom lens according to claim 1, wherein said second lens groupcomprises, in succession from the object side, a negative first lenshaving its surface of sharper curvature facing the image side, apositive meniscus second lens joined to said first lens and having itsconvex surface facing the object side, and a negative third lens havingits surface of sharper curvature facing the object side, and satisfiesthe following conditions: ##EQU6## where n₂₂ : the refractive index ofthe second lens in the second lens groupf₂ : the focal length of thesecond lens group r₂₂ : the radius of curvature of the joined surface ofthe first lens and the second lens in the second lens group r₂₄ : theradius of curvature of that surface of the third lens in the second lensgroup which is adjacent to the object side r₂₅ : the radius of curvatureof that surface of the third lens in the second lens group which isadjacent to the image side.
 3. A telephoto zoom lens according to claim1, wherein said third lens group comprises, in succession from theobject side, a forward positive lens group and a rearward negative lensgroup, said forward positive lens group comprising, in succession fromthe object side, a positive lens having its surface of sharper curvaturefacing the image side, a biconvex positive lens, a negative lens joinedto said biconvex positive lens and having its surface of sharpercurvature of facing the object side, and a positive meniscus lens havingits convex surface facing the object side, and said third lens groupsatisfies the following conditions:

    0.6<f.sub.3F /f.sub.3 <1.3

    1.5<|f.sub.3R /f.sub.3 |<8.5

    0.35<f.sub.3F /f.sub.31 <0.65

where f_(3F) : the focal length of the forward positive lens group inthe third lens group f_(3R) : the focal length of the rearward negativelens group in the third lens group f₃₁ : the focal length of the firstlens in the forward positive lens group in the third lens group.
 4. Atelephoto zoom lens according to claim 1, characterized by the followingdata:

    __________________________________________________________________________    f = 71.500-205.000 (focal length of the entire system)                        F-number 4.1-5.5                                                              __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________    1  r.sub.11                                                                        153.845                                                                              d.sub.1                                                                         2.300 n.sub.11                                                                        1.80458                                                                           25.5 L.sub.11                                       2  r.sub.12                                                                        71.737 d.sub.2                                                                         5.800 n.sub.12                                                                        1.51680                                                                           64.1 L.sub.12                                       3  r.sub.13                                                                        -449.462                                                                             d.sub.3                                                                         0.100                 G.sub.1                                   4  r.sub.14                                                                        107.481                                                                              d.sub.4                                                                         4.600 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                       5  r.sub.15                                                                        -278.364                                                                             d.sub.5                                                                         (variable)                                                      6  r.sub.21                                                                        -228.633                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.69350                                                                           53.8 L.sub.21                                       7  r.sub.22                                                                        18.350 d.sub.7                                                                         4.000 n.sub.22                                                                        1.80458                                                                           25.5 L.sub.22                                       8  r.sub.23                                                                        45.502 d.sub.8                                                                         3.800                 G.sub.2                                   9  r.sub.24                                                                        -33.847                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.69350                                                                           53.8 L.sub.23                                       10 r.sub.25                                                                        550.868                                                                              d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        104.039                                                                              d.sub.11                                                                        4.200 n.sub.31                                                                        1.49782                                                                           82.6 L.sub.31                                       12 r.sub. 32                                                                       -38.434                                                                              d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        52.401 d.sub.13                                                                        5.500 n.sub.32                                                                        1.48749                                                                           70.2 L.sub.32                                       14 r.sub.34                                                                        -31.880                                                                              d.sub.14                                                                        1.400 n.sub.33                                                                        1.74000                                                                           28.3 L.sub.33                                       15 r.sub.35                                                                        -126.224                                                                             d.sub.15                                                                        0.800                                                           16 r.sub.36                                                                        32.945 d.sub.16                                                                        4.600 n.sub.34                                                                        1.62041                                                                           60.3 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        182.768                                                                              d.sub.17                                                                        13.100                                                          18 r.sub.38                                                                        -181.312                                                                             d.sub.18                                                                        1.600 n.sub.35                                                                        1.76684                                                                           46.8 L.sub.35                                       19 r.sub.39                                                                        24.638 d.sub.19                                                                        9.800                                                           20 r.sub.40                                                                        113.747                                                                              d.sub.20                                                                        3.200 n.sub.36                                                                        1.62588                                                                           35.6 L.sub.36                                       21 r.sub.41                                                                        -66.352                                                                  __________________________________________________________________________    f      71.500        115.000                                                                           205.000                                              __________________________________________________________________________    d 5    1.782         24.276                                                                            38.607                                               d 10   16.005        9.748                                                                             0.640                                                B f    55.650        63.190                                                                            83.289                                               __________________________________________________________________________


5. A telephoto zoom lens according to claim 1, characterized by thefollowing data:

    __________________________________________________________________________    f = 71.500-205.000 (focal length of the entire system)                        F-number 4.1-5.5                                                              __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________    1  r.sub.11                                                                        120.465                                                                              d.sub.1                                                                         3.700 n.sub.11                                                                        1.51680                                                                           64.1 L.sub.11                                       2  r.sub.12                                                                        1885.001                                                                             d.sub.2                                                                         0.100                                                           3  r.sub.13                                                                        87.589 d.sub.3                                                                         2.000 n.sub.12                                                                        1.80458                                                                           25.5 L.sub.12                                                                           G.sub.1                                   4  r.sub.14                                                                        52.453 d.sub.4                                                                         7.600 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                       5  r.sub.15                                                                        -413.504                                                                             d.sub.5                                                                         (variable)                                                      6  r.sub.21                                                                        -150.683                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.65160                                                                           58.5 L.sub.21                                       7  r.sub.22                                                                        20.543 d.sub.7                                                                         3.400 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                       8  r.sub.23                                                                        36.361 d.sub.8                                                                         4.200                 G.sub.2                                   9  r.sub.24                                                                        -35.217                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.65160                                                                           58.5 L.sub.23                                       10 r.sub.25                                                                        5931.968                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        106.024                                                                              d.sub.11                                                                        4.500 n.sub.31                                                                        1.50137                                                                           56.5 L.sub.31                                       12 r.sub.32                                                                        - 37.807                                                                             d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        65.312 d.sub.13                                                                        5.300 n.sub.32                                                                        1.51860                                                                           70.1 L.sub.32                                       14 r.sub.34                                                                        -31.533                                                                              d.sub.14                                                                        1.400 n.sub.33                                                                        1.75520                                                                           27.6 L.sub.33                                       15 r.sub.35                                                                        -393.056                                                                             d.sub.15                                                                        0.800                                                           16 r.sub.36                                                                        29.359 d.sub.16                                                                        3.600 n.sub.34                                                                        1.69350                                                                           53.8 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        46.171 d.sub.17                                                                        40.200                                                          18 r.sub.38                                                                        -18.228                                                                              d.sub.18                                                                        2.100 n.sub.35                                                                        1.77279                                                                           49.4 L.sub.35                                       19 r.sub.39                                                                        -29.161                                                                              d.sub.19                                                                        0.200                                                           20 r.sub.40                                                                        1024.571                                                                             d.sub.20                                                                        2.800 n.sub.36                                                                        1.69895                                                                           30.1 L.sub.36                                       21 r.sub.41                                                                        -73.471                                                                  __________________________________________________________________________    f      71.500        115.000                                                                           205.000                                              __________________________________________________________________________    d 5    1.400         24.501                                                                            36.417                                               d 10   16.800        10.418                                                                            0.946                                                B f    41.267        46.675                                                                            69.107                                               __________________________________________________________________________


6. A telephoto zoom lens according to claim 1, characterized by thefollowing data:

    __________________________________________________________________________    f = 71.500-205.000 (focal length of the entire system)                        F-number 4.1-5.5                                                              __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________    1  r.sub.11                                                                        124.745                                                                              d.sub.1                                                                         3.700 n.sub.11                                                                        1.51680                                                                           64.1 L.sub.11                                       2  r.sub.12                                                                        4325.365                                                                             d.sub.2                                                                         0.100                                                           3  r.sub.13                                                                        87.610 d.sub.3                                                                         2.000 n.sub.12                                                                        1.80458                                                                           25.5 L.sub.12                                                                           G.sub.1                                   4  r.sub.14                                                                        52.453 d.sub.4                                                                         7.700 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                       5  r.sub.15                                                                        -416.542                                                                             d.sub.5                                                                         (variable)                                                      6  r.sub.21                                                                        -150.751                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.65160                                                                           58.5 L.sub.21                                       7  r.sub.22                                                                        20.543 d.sub.7                                                                         3.400 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                       8  r.sub.23                                                                        36.370 d.sub.8                                                                         4.200                 G.sub.2                                   9  r.sub.24                                                                        -35.484                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.65160                                                                           58.5 L.sub.23                                       10 r.sub.25                                                                        2543.972                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        103.308                                                                              d.sub.11                                                                        4.500 n.sub.31                                                                        1.50137                                                                           56.5 L.sub.31                                       12 r.sub.32                                                                        -38.149                                                                              d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        64.331 d.sub.13                                                                        5.300 n.sub.32                                                                        1.51860                                                                           70.1 L.sub.32                                       14 r.sub.34                                                                        -31.533                                                                              d.sub.14                                                                        1.400 n.sub.33                                                                        1.75520                                                                           27.6 L.sub.33                                       15 r.sub.35                                                                        -368.870                                                                             d.sub.15                                                                        0.800                                                           16 r.sub.36                                                                        29.048 d.sub.16                                                                        3.600 n.sub.34                                                                        1.69350                                                                           53.8 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        44.423 d.sub.17                                                                        40.200                                                          18 r.sub.38                                                                        -18.138                                                                              d.sub.18                                                                        2.100 n.sub.35                                                                        1.76684                                                                           46.8 L.sub.35                                       19 r.sub.39                                                                        -28.876                                                                              d.sub.19                                                                        0.200                                                           20 r.sub.40                                                                        -4032.012                                                                            d.sub.20                                                                        2.800 n.sub.36                                                                        1.72825                                                                           28.3 L.sub.36                                       21 r.sub.41                                                                        -71.662                                                                  __________________________________________________________________________    f      71.500        135.000                                                                           205.006                                              __________________________________________________________________________    d 5    1.741         28.503                                                                            36.546                                               d 10   16.985        7.923                                                                             1.065                                                B f    40.922        51.636                                                                            68.755                                               __________________________________________________________________________


7. A telephoto zoom lens according to claim 1, characterized by thefollowing data:

    __________________________________________________________________________    f = 71.500-205.000 (focal length of the entire system)                        F-number 4.1-5.5                                                              __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________    1  r.sub.11                                                                        153.844                                                                              d.sub.1                                                                         2.300 n.sub.11                                                                        1.80458                                                                           25.5 L.sub.11                                       2  r.sub.12                                                                        71.737 d.sub.2                                                                         5.800 n.sub.12                                                                        1.51680                                                                           64.1 L.sub.12                                       3  r.sub.13                                                                        -449.461                                                                             d.sub.3                                                                         0.100                 G.sub.1                                   4  r.sub.14                                                                        107.481                                                                              d.sub.4                                                                         4.600 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                       5  r.sub.15                                                                        -278.364                                                                             d.sub.5                                                                         (variable)                                                      6  r.sub.21                                                                        -207.164                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.69350                                                                           53.8 L.sub.21                                       7  r.sub.22                                                                        20.395 d.sub.7                                                                         4.000 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                       8  r.sub.23                                                                        40.805 d.sub.8                                                                         4.000                 G.sub.2                                   9  r.sub.24                                                                        -32.559                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.69350                                                                           53.8 L.sub.23                                       10 r.sub.25                                                                        -687.887                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        104.039                                                                              d.sub.11                                                                        4.200 n.sub.31                                                                        1.49782                                                                           82.6 L.sub.31                                       12 r.sub.32                                                                        -38.434                                                                              d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        52.401 d.sub.13                                                                        5.500 n.sub.32                                                                        1.48749                                                                           70.2 L.sub.32                                       14 r.sub.34                                                                        -31.880                                                                              d.sub.14                                                                        1.400 n.sub.33                                                                        1.74000                                                                           28.3 L.sub.33                                       15 r.sub.35                                                                        -126.223                                                                             d.sub.15                                                                        0.800                                                           16 r.sub.36                                                                        32.945 d.sub.16                                                                        4.600 n.sub.34                                                                        1.62041                                                                           60.3 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        182.768                                                                              d.sub.17                                                                        13.100                                                          18 r.sub.38                                                                        -181.312                                                                             d.sub.18                                                                        1.600 n.sub.35                                                                        1.76684                                                                           46.8 L.sub.35                                       19 r.sub.39                                                                        24.638 d.sub.19                                                                        9.800                                                           20 r.sub.40                                                                        113.747                                                                              d.sub.20                                                                        3.200 n.sub.36                                                                        1.62588                                                                           35.6 L.sub.36                                       21 r.sub.41                                                                        -66.352                                                                  __________________________________________________________________________    f      71.500        115.000                                                                           205.000                                              __________________________________________________________________________    d 5    1.825         24.320                                                                            38.650                                               d 10   15.816        9.559                                                                             0.452                                                B f    55.650        63.190                                                                            83.289                                               __________________________________________________________________________


8. A telephoto zoom lens according to claim 1, characterized by thefollowing data:

    __________________________________________________________________________    f =  71.500- 205.000 (focal length of the entire system)                      F-number 4.1- 5.5                                                             __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________     1 r.sub.11                                                                        118.310                                                                              d.sub.1                                                                         2.300 n.sub.11                                                                        1.80458                                                                           25.5 L.sub.11                                        2 r.sub.12                                                                        63.790 d.sub.2                                                                         6.000 n.sub.12                                                                        1.51680                                                                           64.1 L.sub.12                                        3 r.sub.13                                                                        1325.679                                                                             d.sub.3                                                                         0.100                 G.sub.1                                    4 r.sub.14                                                                        95.278 d.sub.4                                                                         5.400 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                        5 r.sub.15                                                                        -289.179                                                                             d.sub.5                                                                         (variable)                                                       6 r.sub.21                                                                        -155.511                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.65160                                                                           58.5 L.sub.21                                        7 r.sub.22                                                                        20.550 d.sub.7                                                                         3.400 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                        8 r.sub.23                                                                        36.637 d.sub.8                                                                         4.200                 G.sub.2                                    9 r.sub.24                                                                        -34.912                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.65160                                                                           58.5 L.sub.23                                       10 r.sub.25                                                                        2426.367                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        115.890                                                                              d.sub. 11                                                                       3.500 n.sub.31                                                                        1.51860                                                                           70.1 L.sub.31                                       12 r.sub.32                                                                        -84.561                                                                              d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        50.935 d.sub.13                                                                        4.300 n.sub.32                                                                        1.48749                                                                           70.2 L.sub.32                                       14 r.sub.34                                                                        -88.680                                                                              d.sub.14                                                                        0.800                                                           15 r.sub.35                                                                        38.863 d.sub.15                                                                        5.200 n.sub.33                                                                        1.51680                                                                           64.1 L.sub.33                                       16 r.sub.36                                                                        -54.825                                                                              d.sub.16                                                                        1.400 n.sub.34                                                                        1.78470                                                                           26.1 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        145.469                                                                              d.sub.17                                                                        39.800                                                          18 r.sub.38                                                                        -19.312                                                                              d.sub.18                                                                        2.100 n.sub.35                                                                        1.77279                                                                           49.4 L.sub.35                                       19 r.sub.39                                                                        -32.084                                                                              d.sub.19                                                                        0.200                                                           20 r.sub.40                                                                        -701.705                                                                             d.sub.20                                                                        2.800 n.sub.36                                                                        1.74077                                                                           27.6 L.sub.36                                       21 r.sub.41                                                                        -64.629                                                                  __________________________________________________________________________    f      71.500        115.000                                                                           205.000                                              __________________________________________________________________________    d 5    1.586         25.921                                                                            37.783                                               d 10   17.300        11.136                                                                            1.853                                                B f    42.725        47.511                                                                            70.890                                               __________________________________________________________________________


9. A telephoto zoom lens comprising, in succession from the object side,a first lens group having a positive refractive power, a second lensgroup having a negative refractive power and a third lens group having apositive refractive power, said second lens group comprising, insuccession from the object side, a negative lens having its surface ofsharper curvature facing the image side, a positive meniscus lens joinedto said negative lens and having its convex surface facing the objectside, and a negative lens having its surface of sharper curvature facingthe object side, said lens groups being moved during zooming andsatisfying the following conditions: ##EQU7## where n₂₂ : the refractiveindex of the second lens in the second lens groupf₂ : the focal lengthof the second lens group r₂₂ : the radius of curvature of the joinedsurface of the first lens and the second lens in the second lens groupf₂₄ : the radius of curvature of that surface of the third lens in thesecond lens group which is adjacent to the object side r₂₅ : the radiusof curvature of that surface of the third lens in the second lens groupwhich is adjacent to the image side.
 10. A telephoto zoom lens accordingto claim 9, satisfying the following conditions:

    1.3<f.sub.1 /f.sub.W <1.6

    0.25<|f.sub.2 /f.sub.W |<0.45

    0.44<f.sub.3 /f.sub.W <0.52

where f_(W) : the focal length of the entire system at the wide end f₁ :the focal length of the first lens group f₃ : the focal length of thethird lens group.
 11. A telephoto zoom lens according to claim 9,wherein said third lens group comprises a forward group having apositive refractive power and a rearward group having a negativerefractive power, and satisfies the following conditions:

    0.6<f.sub.3F /f.sub.3 <1.3

    1.5<|f.sub.3R /f.sub.3 |<8.5

where f_(3F) : the focal length of the forward group in the third lensgroup f_(3R) : the focal length of the rearward group in the third lensgroup.
 12. A telephoto zoom lens according to claim 9, characterized bythe following data:

    __________________________________________________________________________    f = 71.500- 204.999 (focal length of the entire system)                       F-number 4.1- 5.5                                                             __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________     1 r.sub.11                                                                        98.438 d.sub.1                                                                         3.500 n.sub.11                                                                        1.46450                                                                           65.8 L.sub.11                                        2 r.sub.12                                                                        802.616                                                                              d.sub.2                                                                         0.100                                                            3 r.sub.13                                                                        76.116 d.sub.3                                                                         2.000 n.sub.12                                                                        1.80458                                                                           25.5 L.sub.12                                                                           G.sub.1                                    4 r.sub.14                                                                        44.695 d.sub.4                                                                         7.300 n.sub.13                                                                        1.51835                                                                           60.3 L.sub.13                                        5 r.sub.15                                                                        -279.389                                                                             d.sub.5                                                                         (variable)                                                       6 r.sub.21                                                                        -128.684                                                                             d.sub.6                                                                         1.200 n.sub.21                                                                        1.65160                                                                           58.5 L.sub.21                                        7 r.sub.22                                                                        20.994 d.sub.7                                                                         3.200 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                        8 r.sub.23                                                                        37.184 d.sub.8                                                                         4.100                 G.sub.2                                    9 r.sub.24                                                                        -37.845                                                                              d.sub.9                                                                         1.200 n.sub.23                                                                        1.65160                                                                           58.5 L.sub.23                                       10 r.sub.25                                                                        6107.025                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        119.160                                                                              d.sub.11                                                                        4.300 n.sub.31                                                                        1.50137                                                                           56.5 L.sub.31                                       12 r.sub.32                                                                        -37.088                                                                              d.sub.12                                                                        0.200                                                           13 r.sub.33                                                                        71.445 d.sub.13                                                                        5.300 n.sub.32                                                                        1.51860                                                                           70.1 L.sub.32                                       14 r.sub.34                                                                        -29.228                                                                              d.sub.14                                                                        1.400 n.sub.33                                                                        1.75520                                                                           27.6 L.sub.33                                       15 r.sub.35                                                                        -333.136                                                                             d.sub.15                                                                        0.800                                                           16 r.sub.36                                                                        22.903 d.sub.16                                                                        3.600 n.sub.34                                                                        1.54814                                                                           45.9 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        38.213 d.sub.17                                                                        34.800                                                          18 r.sub.38                                                                        -15.897                                                                              d.sub.18                                                                        2.100 n.sub.35                                                                        1.77279                                                                           49.4 L.sub.35                                       19 r.sub.39                                                                        -24.699                                                                              d.sub.19                                                                        0.200                                                           20 r.sub.40                                                                        -306.837                                                                             d.sub.20                                                                        2.800 n.sub.36                                                                        1.86074                                                                           23.0 L.sub.36                                       21 r.sub.41                                                                        -82.419                                                                  __________________________________________________________________________    f      71.500        135.000                                                                           204.999                                              __________________________________________________________________________    d 5    2.250         22.806                                                                            29.375                                               d 10   19.898        8.849                                                                             0.957                                                B f    41.337        53.103                                                                            69.563                                               __________________________________________________________________________


13. A telephoto zoom lens according to claim 9, characterized by thefollowing data:

    __________________________________________________________________________    f =  72.318- 205.565 (focal length of the entire system)                      F-number 4.5- 5.0                                                             __________________________________________________________________________       Radius of                                                                              Center thickness                                                                      Refractive                                                                          Abbe                                                   curvature                                                                              and space                                                                             index number                                              No.                                                                              r        d       n     ν                                                __________________________________________________________________________     1 r.sub.11                                                                        107.200                                                                              d.sub.1                                                                         3.850 n.sub.11                                                                        1.51680                                                                           64.1 L.sub.11                                        2 r.sub.12                                                                        -1450.001                                                                            d.sub.2                                                                         0.200                                                            3 r.sub.13                                                                        79.420 d.sub.3                                                                         1.950 n.sub.12                                                                        1.80518                                                                           25.4 L.sub.12                                                                           G.sub.1                                    4 r.sub.14                                                                        47.810 d.sub.4                                                                         6.300 n.sub.13                                                                        1.51680                                                                           64.1 L.sub.13                                        5 r.sub.15                                                                        -1449.991                                                                            d.sub.5                                                                         (variable)                                                       6 r.sub.21                                                                        -203.083                                                                             d.sub.6                                                                         1.000 n.sub.21                                                                        1.69680                                                                           55.6 L.sub.21                                        7 r.sub.22                                                                        20.547 d.sub.7                                                                         3.860 n.sub.22                                                                        1.86074                                                                           23.0 L.sub.22                                        8 r.sub.23                                                                        37.163 d.sub.8                                                                         3.200                 G.sub.2                                    9 r.sub.24                                                                        -38.171                                                                              d.sub.9                                                                         1.000 n.sub.23                                                                        1.69680                                                                           55.6 L.sub.23                                       10 r.sub.25                                                                        -497.113                                                                             d.sub.10                                                                        (variable)                                                      11 r.sub.31                                                                        85.720 d.sub.11                                                                        4.550 n.sub.31                                                                        1.61272                                                                           58.6 L.sub.31                                       12 r.sub.32                                                                        -31.160                                                                              d.sub.12                                                                        1.000 n.sub.32                                                                        1.71736                                                                           29.5 L.sub.32                                       13 r.sub.33                                                                        -54.350                                                                              d.sub.13                                                                        0.200                                                           14 r.sub.34                                                                        27.615 d.sub.14                                                                        5.160 n.sub.33                                                                        1.48749                                                                           70.2 L.sub.33                                       15 r.sub.35                                                                        -88.000                                                                              d.sub.15                                                                        2.940                                                           16 r.sub.36                                                                        -55.000                                                                              d.sub.16                                                                        2.000 n.sub.34                                                                        1.75520                                                                           27.6 L.sub.34                                                                           G.sub.3                                   17 r.sub.37                                                                        0.000  d.sub.17                                                                        36.100                                                          18 r.sub.38                                                                        -17.300                                                                              d.sub.18                                                                        1.270 n.sub.35                                                                        1.69680                                                                           55.6 L.sub.35                                       19 r.sub.39                                                                        -30.500                                                                              d.sub.19                                                                        0.200                                                           20 r.sub.40                                                                        700.000                                                                              d.sub.20                                                                        2.480 n.sub.36                                                                        1.71736                                                                           29.5 L.sub.36                                       21 r.sub.41                                                                        -68.001                                                                  __________________________________________________________________________    f      72.818        133.831                                                                           205.565                                              __________________________________________________________________________    d 5    .939          25.106                                                                            32.939                                               d 10   20.091        10.046                                                                            1.650                                                B f    42.052        49.813                                                                            64.511                                               __________________________________________________________________________